1. Field of the Invention
The present invention relates to a terminal apparatus, a recording medium on which a program is recorded, and a method which measure a usable communication bandwidth when carrying out a data communication between terminal apparatus, in a communication system in which a plurality of terminal apparatus are connected via a network.
2. Description of the Related Art
With a terminal apparatus connected to a network (a communication network) such as an internet, it can happen that a usable communication bandwidth when carrying out a data communication with another terminal apparatus via the network fluctuates greatly depending on conditions such as an area, a provider and a time. For this reason, the communication bandwidth varies according to the terminal apparatus.
Consequently, in a case of carrying out a communication among a plurality of terminal apparatus, or between a server apparatus and a terminal apparatus, via the network, by measuring a usable communication bandwidth for each terminal apparatus, and carrying out a communication control in accordance with a measurement result, it is possible to realize a low-burden data communication.
For example, with a content distribution system which, by a plurality of terminal apparatus connected via the network transmitting and receiving among themselves content information which each terminal apparatus holds, enables a distribution of the content information (for example, refer to Japanese Unexamined Patent Publication No. 2006-197400), in a case in which moving image content information is streaming distributed from a certain terminal apparatus to another terminal apparatus, it is possible to realize a pleasing moving image distribution by distributing at an image quality suited to the usable communication bandwidth. Specifically, with a terminal apparatus which can select between a moving image distribution of 1 Mbps and a moving image distribution of 100 kbps, in a case in which a usable communication bandwidth of another terminal apparatus, which receives a moving image distribution from the terminal apparatus, is 100 kbps, it is possible to realize a pleasing moving image distribution appropriate to the usable communication bandwidth by selecting a bit rate of 100 kbps.
Meanwhile, as a method of measuring the communication bandwidth, there is one in which a bandwidth measurement server apparatus is installed in a data center or the like, and the communication bandwidth is measured by carrying out a communication between the bandwidth measurement server apparatus and the terminal apparatus (for example, refer to Non-patent Document “goo speed test”, [online], NTT Resonant Inc., [searched for Oct. 25, 2007], Internet<URL:http://speedtest.go.ne.jp/flash.htm>). FIG. 8 is a diagram showing a configuration of a heretofore known communication system which measures a communication bandwidth. The communication system is configured including a plurality of terminal apparatus 1001A to 1001E, and a bandwidth measurement server apparatus 1000, which measures a usable communication bandwidth of each terminal apparatus 1001A to 1001E in a network 1002. Each terminal apparatus 1001A to 1001E, and the bandwidth measurement server apparatus 1000, are connected via the network 1002. With this kind of communication system, the bandwidth measurement server apparatus 1000, by downloading or uploading predetermined measurement data at a predetermined measurement bit rate from or to each terminal apparatus 1001A to 1001E, measures the communication bandwidth for each of the terminal apparatus 1001A to 1001E based on a transmission time or reception time of the data.